We present evidence on the effects of exogenous heating by water bath (WB) and magnetic hyperthermia (MHT) on a glial micro-tumor phantom. To this, magnetic nanoparticles (MNPs) of 30–40 nm were designed to obtain particle sizes for maximum heating efficiency. The specific power absorption (SPA) values (f = 560 kHz, H = 23.9 kA/m) for as prepared colloids (533–605 W/g) dropped to 98–279 W/g in culture medium. The analysis of the intracellular MNPs distribution showed vesicle-trapped MNPs agglomerates spread along the cytoplasm, as well as large (~0.5–0.9 μm) clusters attached to the cell membrane. Immediately after WB and MHT (T = 46 °C for 30 min) the cell viability was ≈70% and, after 4.5 h, decreased to 20–25%, demonstrating that metabolic processes are involved in cell killing. The analysis of the cell structures after MHT revealed a significant damage of the cell membrane that is correlated to the location of MNPs clusters, while local cell damage were less noticeable after WB without MNPs. In spite of the similar thermal effects of WB and MHT on the cell viability, our results suggest that there is an additional mechanism of cell damage related to the presence of MNPs at the intracellular space.

Polycrystalline transparent Zinc oxide thin films have been grown on glass substrates by the sol–gel technique using two different precursor solutions. The physical properties of the films were analyzed with X-ray diffraction, Atomic Force Microscopy, UV–Vis and Raman spectroscopy. The results show that the films grew in the hexagonal wurtzite structure. The band gap of the samples was estimated from UV–Vis measurements in values from 3.1 to 3.22eV, these values are in agreement with those reported in the literature. Two different simple ways to obtain polycrystalline ZnO were developed and the properties of the films were studied as a function of the precursor solution